The present invention relates to a camera with a built-in zoom lens, and more particularly, to a camera provided with a drive mechanism for a zoom lens built-in a compact camera or the like.
Conventional cameras with a zoom lens are generally of the lens interchangeable system and a zooming mechanism for an interchangeable lens of the system has been disclosed, for example, in Japanese Laid-Open Patent Application No. Sho 54/1979-771312. As a lens shutter camera, an AF lens drive mechanism in a fully automatic camera which employs a lens shutter has been disclosed in Japanese Laid-Open Patent Applications Nos. Sho 56/1981-52709 and Sho 60/1985-93409. However, this lens drive mechanism is not for a zoom lens but for a lens system which is supported on a single frame body to which a guide shaft is secured.
Furthermore, a technique for incorporating a macro photographing mechanism in a camera with a built-in zoom lens as described above so as to enable a macro photography is not yet proposed. As such a camera enabling a macro photography, an interchangeable zoom lens provided with a macro photographying mechanism has been disclosed, for example, in Japanese Laid-Open Patent Application No. Sho 52/1977-45330 and an apparatus for moving an optical system in a variable focus camera has been disclosed in Japanese Laid-Open Patent Applications Nos. Sho 59/1984-191021 and Sho 59/1984-177523 (U.S. Pat. No. 4,536,068).
In a zooming mechanism and a macro photographing mechanism of an interchangeable lens which employ a cam barrel which is generally used in an interchangeable lens, there are problems of necessitating a highly accurate cam and hence increasing its manufacturing cost. In addition, when a shutter lens is employed, a space and a configuration of the cam barrel are restricted since a shutter mechanism is disposed within the cam barrel.
In addition, although it is conceivable to drive each of the lens groups in a zoom lens system by a cam mechanism, this disadvantageously complicates the mechanism. In a macro photographing mechanism, although it is conceivable that the number of steps of a focus adjusting cam in a lens shutter mechanism increases to a macro photographing region, a full movement of front elements in a lens group is technically limited, so that it is disadvantageously impossible to make a magnification of a picture in a macro photography larger.